Preliminary Research On Distribution Pattern Of Betula Fruticosa Var. Ruprechtiana Trauty. In Jinchuan Mire-Wetland

Jinchuan mire-wetland wetland has located on east Jilin province——Huinan county,Changbai Mountain north slpoes and Longgang moutain middle. This paper has studied on the Betula fruticosa var. ruprechtiana Trauty. population and environmental factors and the relationships between them,by the CCA ordination way,find out the main environmental impact factors that has influence on the Betula fruticosa var. ruprechtiana Trauty. population distribution. According to the distance from the river and the Betula fruticosa var. ruprechtiana Trauty. species distribution,set up two transect with eight plots. Conclusions were as follows:1. Based on age composition, Betula fruticosa var. ruprechtiana Trauty. population's population can be divided into two categories:Ⅰ. Betula fruticosa var. ruprechtiana Trauty. in plots farther from the river have a certain degree of growth population characteristics.Ⅱ. Betula fruticosa var. ruprechtiana Trauty. in plots close to the river have a more obvious characteristics of the stability populations.2. Betula fruticosa var. ruprechtiana Trauty. population in the 8 survey plots showed three categories distribution pattern:Ⅰ. Betula fruticosa var. population in plots that have lower water level and farther from the river showing a random distribution pattern at various scales .Ⅱ. Distribution pattern of Betula fruticosa var. ruprechtiana Trauty. population in plots at northwest of the wetland showed: there is aggregated distribution in smaller scaler, and then as the scale increases, aggregation levels declined, while showing a random distributtion pattern.Ⅲ. Betula fruticosa var. ruprechtiana Trauty. population at the sourth of the wetland close to the river and on a higher water level, it showing the aggregation distribution pattern trend or have little change as the scale increases.3. Other shrubs have little effects on the distribution of Betula fruticosa var. ruprechtiana Trauty. population. The distribution of Betula fruticosa var. ruprechtiana Trauty. population was primarily affected by its own characteristics and environmental factors.4. According to CCA results suggest: The environmental factors primarily affect the distribution of Betula fruticosa var. ruprechtiana Trauty. population are water level, water pH and total nitrogen content, but the soil nutrient has little influence on it. According to the characteristics of environmental factors, the eight quadrats can be divided into:Ⅰ, Stronger acidity, have a certain degree of growth population characteristics.Ⅱ, Lower water level and poor nurtion in water, have growth population characteristics and random distribution pattern at large scales .Ⅲ, Well nourished in water, have obvious characteristics of the stability populations.